Satii Chemistry Official Thread

Test Preparation
101

<p>what was the question about when does an atom emit/absorb energy/light? i put that it is emitted in discrete numbers called quanta. Ugh, my time management sucked on that.</p>

102

<p>well PR is a lot easier...</p>

<p>and i dont believe u finished in 30 minutes on sat2 history</p>

103

<p>yea quanta was the answer</p>

104

<p>is mole fraction just moles X/ total moles? sorry we didnt cover these things in IB chem</p>

105

<p>yeah it is. What did you guys get for the Na---- * x H2O problem?</p>

106

<p>It was 10.</p>

107

<p>yeah on that problem i had to guess
but i vaguely remember from chem labs that it might have been 10 for x</p>

108

<p>i put damn water vapor h20 as the least found in the atmosphere. it's h2. DAMMIT!</p>

109

<p>arent photon the discrete particles, wat are quanta</p>

110

<p>yea, H2 is the least found</p>

111

<p>do i lose 1/4 of point for getting CE problems wrong???</p>

112

<p>i think it is 1/3</p>

113

<p>thats wat my friend told me who took the test last year</p>

114

<p>nope.. it cannot be 1/3....</p>

115

<p>yea i was wondering too, i hope they dont take off nething</p>

116

<p>Copper is a transition element, and don't they dissolve into colored ions in a water solution? I put T and then F, because alkali metals are MUCH more reactive than copper.</p>

117

<p>i think quanta are 'packets' of energy.</p>

<p>arg, and the CE grading thing is just so unfair. arg</p>

<p>EDIT: packets of energy: "Light can carry energy only in specific amounts, proportional to the frequency, as though it came in packets. The term quanta was given to these discrete packets of electromagnetic energy by Max Planck."</p>

118

<p>so then photons are the discrete particles not quanta so that cannot be the answer</p>

119

<p>a quantum is the amount of energy it takes for an electron to jump up a single energy level. When it falls back down, it releases a photon, which consists of a quantum of energy.</p>

<p>Quanta was the answer.</p>

120

<p>no, cuz discrete means they are whole number integers. I think it was Planck who is discovered that light always travels in integers multiples.</p>

<p>it's like 'discrete' mathematics.</p>